The related regulations for electric power industry stipulate that CO gas is an important component to be detected when analyzing the gas composition of SF6 equipment. In this study, based on the photoacoustic spectroscopy technology, the quantitative gas detection of CO is carried out. First, in order to avoid the cross-interference effects of other component gases on photoacoustic spectroscopy detection of CO, the characteristic absorption spectrum of CO in 4291.5 cm−1 (whose wavelength is 2330.2 nm) is determined. Second, the nonresonant photoacoustic cell is optimized in this study. After that, designing and building a trace gas photoacoustic spectroscopy detection platform around the developed photoacoustic cell, using the built detection platform to perform photoacoustic spectroscopy detection of the concentration of CO, and obtaining photoacoustic signals of different concentrations of CO, the photoacoustic signals increase linearly as the concentration increases. With SF6 as the background gas, the lower detection limit of CO gas reaches 20.5 ppm, and with N2 as the background gas, it reaches 5.6 ppm. After all, the influence mechanism of the background gas on the photoacoustic signal is studied, and based on the influence mechanism, the lower detection limit of CO with the background gas of different mixing ratios of SF6/N2 is predicted. The verified experiment is basically consistent with the predicted results, which proves the accuracy of the forecast. This study provides guidance for the engineering application of CO photoacoustic spectroscopy detection in SF6 equipment.

中文翻译：

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气体绝缘设备中CO光声光谱检测研究


电力行业相关法规规定，在分析SF6设备气体成分时，CO气体是需要检测的重要成分。本研究基于光声光谱技术，开展了CO气体的定量检测。首先，为了避免其他组分气体对CO光声光谱检测的交叉干扰影响，确定了CO在4291.5 cm−1（波长为2330.2 nm）处的特征吸收光谱。其次，本研究对非共振光声电池进行了优化。之后，围绕所研制的光声池设计搭建痕量气体光声光谱检测平台，利用搭建的检测平台对CO浓度进行光声光谱检测，得到不同浓度CO的光声信号，光声信号线性增加随着浓度的增加。以SF6为背景气体，CO气体的检测下限达到20.5 ppm，以N2为背景气体，达到5.6 ppm。最后研究了背景气体对光声信号的影响机制，并根据影响机制​​预测了不同SF6/N2混合比背景气体下CO的检出下限。验证实验与预测结果基本一致，证明了预测的准确性。该研究为CO光声光谱检测在SF6设备中的工程应用提供指导。